1. Field of the Invention
This invention generally relates to a magnetic record/playback apparatus, and more particularly to a magnetic record/playback apparatus having an automatic music sensing mechanism.
2. Description of the Prior Art
In scanning tape players, to select a desired song from plural songs recorded on a cassette tape by obtaining a cue for the song by an automatic music sensing means, a tape is driven in a cue scanning fast-forward or rewind mode (hereinafter referred to as a "FF/REW mode"). A cue signal recorded on the tape, indicating the begining of the desired song, is detected by a magnetic head. Then, the cassette drive system is released from the FF/REW mode by the signal and the apparatus is put into an ordinary playback mode. More particularly, to effect an automatic music sensing operation in the cassette deck, it is essential that (1) the tape be driven in the FF/REW mode and (2) the tape be kept in contact with the head while being driven in the FF/REW mode. In general, however, to establish the FF/REW mode in a cassette deck, it is necessary to detach a pinch roller from a capstan shaft of the tape driving system or alternatively an idler of a reel shaft driving system by insituting a changeover operation. The distance of the displacement of the pinch roller caused by such a changeover operation is much larger than the displacement distance of the head in retiring from a record/playback position to an automatic music sensing position. However, the conventional FF/REW mechanism is so designed that a head and its pinch roller are mounted on a single head plate, and the driving system is adapted to be changed over by the displacement of the head plate. Therefore, when the deck is put into the scanning mode by displacement of the head plate, the head is separated too far away from the tape to detect the cue signal on the tape. On the other hand, when the head plate is brought into a position where the head can lightly contact the tape, the tape driving system cannot fully be put into the scanning mode with the pinch roller fully disengaged.